How should you work up calvarium or other osseous lesions when found during the initial staging of a patient with a new diagnosis of NSCLC otherwise non-metastatic?

In general, I try to "prove" metastatic disease to ensure appropriate staging. I have had several situations where a skull or other osseous lesion is suspicious on CT and have tried to assess by PET or NM bone scan - ultimately though, have referred for biopsy and have actually diagnosed several int...